THE PROTOZOA OF THE SEA SHOES 



107 



through each hole in the shell. These threads correspond exactly 

 in function with the blunt pseudopodia of the amoeba. Should 

 they come in contact with a particle of suitable food-material, they 

 immediately surround it, and rapidly retracting, draw the particle 

 to the surface of the body. The threads then completely envelop 

 the food, coalescing as soon as they touch, thus bringing it 

 within the animal. 



The foraminif er multiplies by fission, or by a process of budding. 

 In some species the division of the protoplasm is complete, as in 

 the case of amoebae, so that each animal has its own shell which 



encloses a single chamber, 

 but in most cases the ' bud ' 

 remains attached to a parent 

 cell, and develops a shell 

 that is also fixed to the 



Fro. 57. THE SAME FOHAMINIFEB 



(FlO. 56) AS SEEN WHEN ALIYE 



FIG. 58. SECTION OF THE SHELL 

 OF A COMPOUND FORAMINPFER 



shell of its progenitor. The 

 younger animal thus pro- 

 duced from the bud gives 

 rise to another, which de- 

 velops in the same manner ; 



and this process continues, the new bud being always produced on 

 the newest end, till, at last, a kind of colony of protozoons is formed, 

 their shells remaining attached to one another, thus producing a 

 compound shell, composed of several chambers, arranged in the 

 form of a line or spiral, and communicating by means of their per- 

 forated partitions. It will now be seen that each ' cell ' of the 

 compound protozoon feeds not only for itself, but for all the members 

 of its colony, since the nourishment imbibed by any one is capable 

 of diffusion into the surrounding chambers, the protoplasm of the 



